The study was conducted by Tongtiegang Zhao and Shoutang Xiong of Sun Yat-sen University, together with Bingyao Zhang and Yu Li of Dalian University of Technology. The team quantified the lifetime cumulative heatwave exposure of Chinese birth cohorts under future climate change scenarios. They found that younger cohorts will face substantially higher lifetime heatwave exposure, and that regions with lower economic development will face greater challenges from the mismatch between future heat hazards and limited adaptive capacity.
Under global warming, heatwaves are becoming more frequent and intense, but their impacts are not evenly distributed across populations. Previous studies focused mainly on how heatwave characteristics change over specific periods, while the cumulative exposure that different birth cohorts experience over their lifetimes remains poorly understood. This study combines climate projections from the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) with demographic and socioeconomic data to evaluate lifetime heatwave exposure across China.
Future emission pathways strongly affect lifetime heatwave exposure. Under the high-emission scenario (RCP8.5), the annual probability of heatwave occurrence in China is projected to rise from 4.95% to 78.84% by 2099. Because younger cohorts will experience more frequent and intense heat extremes over longer parts of their lives, their cumulative exposure increases markedly. The median lifetime cumulative exposure of the 2020 birth cohort is about four times that of the 1990 cohort.
Climate change is widening inequalities both between generations and across regions. Because warming is projected to be stronger in western China, that region is likely to see larger increases in lifetime heatwave exposure. Meanwhile, many regions with lower economic development have limited adaptive capacity, creating a clear mismatch between future heat hazards and socioeconomic resilience.
By extending the assessment of heatwave impacts from individual events to lifetime cumulative exposure, this study offers insight into how climate change reshapes long-term risks across birth cohorts and regions. The findings indicate that both climate exposure and socioeconomic vulnerability need to be considered when developing adaptation strategies.
See the article:
Xiong S, Zhao T, Zhang B, Li Y. 2026. Lifetime exposure and vulnerability to heatwaves across birth cohorts in China under climate change. Science China Earth Sciences, 69(8): 2900–2911, https://doi.org/10.1007/s11430-025-1956-5
Science China Earth Sciences